This Is AuburnElectronic Theses and Dissertations

Natural History and Conservation of the Eyelash Palmpitviper (Bothriechis schlegelii) in Western Panamá

Date

2007-12-15

Author

Sorrell, Geoffrey

Type of Degree

Thesis

Department

Biological Sciences

Abstract

The focus of this thesis was to examine various components of the natural history, ecology, and conservation biology of the Bothriechis schlegelii. The sections that follow include studies of foraging ecology, demography, and effects of fragmentation on Bothriechis schlegelii. In the first section I examined the effects of color, body size, and sex on growth and survival in an arboreal Neotropical snake, the eyelash palm-pitviper, Bothriechis schlegelii. This species exhibits polychromatism in populations throughout its range. Growth and survival were estimated during a seven-year, mark-recapture study of a population in western Panamá. My results indicate that body size has the strongest vi influence on growth and that sex and color morph have little impact on this variable. Sex had the greatest ability to explain variation in survival whereas body size and color were less informative. However, sex and body size were correlated in this species because females grew to a larger size than males. The second section focuses on movement and foraging ecology of Bothriechis schlegelii. This species is reported to be a nocturnal ambush predator that preys upon a wide variety of vertebrates. However, this study demonstrates that B. schlegelii has a greater temporal activity range than previously documented. Specifically, I document that this snake moves most frequently at night, is capable of capturing mobile prey from daytime perches, and consumes diurnally- and nocturnally-active prey. An ability to consume prey during both night and day increases the importance of the role of B. schlegelii as a predator of small vertebrates. The final section of my thesis examines the response of Bothriechis schlegelii to anthropogenic fragmentation. Cattle production has had a widespread impact on the Neotropical landscape, which has increased in closing decades of the twentieth century. Although the deleterious effects of conversion of native vegetation to pasture have been acknowledged, research on mitigation of such practices is lacking. In this study I focus on the use of tree islands in pasture by an arboreal predator, the eyelash palm-pitviper (Bothriechis schlegelii). The effects of tree island isolation, size, and structural heterogeneity, on snake occupancy were measured. My results indicate that isolation form intact forest, and the structural heterogeneity found within islands were the most important predictors of snake occupancy. Management implications are discussed in light of these findings.